Field of the Invention
The present disclosure relates to a technical field of image display, more particularly, relates to a method and a system for improving RGBW image saturation degree.
Description of the Related Art
In the image display field, since the RGB three color system has a low light mixing efficiency and thus outputs a white light with poor color rendering index, it is replaced by the four color RGBW system gradually. The RGBW four color system not only includes red pixels (R), green pixels (G) and blue pixels (B), but also includes brightness enhanced pixels (W) so as to completely achieve all of functions which may be achieved by the RGB three color system. The four color RGBW system has advantages of high optical efficiency and high color rendering index.
However, as W sub-pixels are added into the RGBW four color system, the saturation degree of pure colors in the image may be degraded. Specifically, the absolute digital values of pure colors in a RGBW display are same to those in a RGB display. However, when the RGBW display includes the background, as the brightness of the background caused by the W sub-pixels is greater than the brightness of the RGB display, the pure colors in the background of the RGBW display look relatively dark, i.e., the brightness of the pure colors is degraded relatively. In comparison with the RGB display, the saturation degree of the pure colors of the RGBW display is degraded relatively due to poor relative brightness.